(Pseudo)dynamic data generation in JMeter

What if you have to do extensive performance tests for a complicated webapp with login, search forms, etc.? If the tool you would use for this must be very powerful, opensource and have graphic interface – there is no way you can pass by JMeter. At this time I’ll tell about how to get dynamical data to be used inside JMeter tests. I’ll presume you’ve already worked with JMeter before and have at least knowhow about a standard test plan structure.